internet connection

I cannot connectup to my server. I cannot hear any dial up tone, yet on my pc it has the modemlisted on my pc. I have uninstalled the modemand then reinstalled it, but still no luck. As my computer is now 4 yrs old, is it worthwhile buying a new modem? and if I do how do I install it in the pc box. If I buy a new modem and it still doesn't work, what would I do next? I have installed my server disc correctly, but cannot dial up to the internet. I have checked my internet settings over and over, but nothing haschanged. Please can you offer some advice?